The purpose of this Exploratory Center for Cheminformatics Research (ECCR) P20 planning grant is to develop a mechanism for bringing together and stimulating collaborative pilot projects among a constantly-evolving nucleus of experts in Cheminformatics-related fields ranging from methods of encoding and capturing molecular information, to machine learning and data mining techniques, to predictive model development, validation, interpretation and utilization. In addition to these research efforts, the Center will bring together a set of domain specialists and application scientists who will serve as both data generators and end users of the knowledge provided by the molecular property models and modeling methods developed during the course of the grant. This group will also test the new Cheminformatics software that will constitute a tangible, deliverable product from this work. Ten application project modules that exemplify possible interactions between various groups and areas of expertise within the Center are presented as part of this proposal. The unifying vision behind the proposed Center is that much of what is done in each of the subdisciplines represented here can be expressed in a Cheminformatics context: The many diverse project areas can be grouped into one or more overlapping categories: "Data Generators" (those who use either theoretical or experimental methods for creating or extracting knowledge), "Machine Learning and Datamining" groups (who perform model validation, feature selection, pattern recognition, generation of potentials of mean force and knowledge-based potential work), as well as "Property-Prediction" groups (who perform chemically-aware model building, molecular property descriptor generation, Quantitative Structure-Property Relationship modeling, validation, and interpretation), and "Application" groups who utilize the information made available using the new tools and methods that are developed as part of the Center. It is our strong belief that these areas of expertise can be brought together within this Planning Grant proposal to generate something larger than the sum of the parts. The Exploratory Center will seed new interdisciplinary projects and train graduate students in these areas. Relevance: Advances in the generation, mining and analysis of chemical information is crucial to the development of new drug therapies, and to modern methods of bioinformatics and molecular medicine.